One trick we use is to take cloth athletic tape and wrap around the hoof 3 times. As the hoof heats up, the adhesive sticks the boot to the hoof wall.
We use the boots for hunting, packing, and endurance riding. If doing 50-mile rides, we'll use some Sika-Flex glue. If doing a 100, glue-on boots without gaiters are what I'd recommend. But for anything <25 miles per day, the Gloves are great, and hold on through some serious bogs. Back-country boots are the same shell with a different gaiter. My neighbor hasn't had any issues, but I think a horse going fast may have some trouble keeping them on (which is why they aren't recommended for endurance by the company).
One nice thing about boots is the lack of noise. You don't "click-clack" down the trail, but instead sound more natural.
I have left Gloves on for a week with the athletic tape or Sika-Flex. I wouldn't hesitate to do 2 weeks.
If you're just carrying a back-up, you might consider just the old EasyBoot, if they still make them.
One other concern I had about leaving them on is going through creeks and such is getting small rocks or sand in them. I was thinking it would be necessary to take them off in the evenings and clean them out and let them dry???
When you say they are best fit if you have to pound them on, are they also difficult to remove?
Check out the Blog at EasyCare. It covers a lot of these issues.
Are they difficult to remove? Well, yes. But generally come off without tools. When I've had to use tools, a flat screwdriver works fine. They are re-usable, and I'd say we generally get a couple hundred miles per boot. Generally, the gaiter wears out and it's a matter of just replacing the gaiter. (The gaiters need re-design if you ask me.) We've worn holes in the toes of a few within 100 miles, but those have been particularly tough rides, and they're still functional.
I'm not telling anyone what to do, but I'll say we use them a lot, and they work great, though there is a learning curve.
For instance, I have one horse who we don't use much anymore. He's basically retired. But we will pull him out of retirement like we did last weekend for some light riding and packing. Gloves are great for that. No need for him to be shod all summer for the 30 miles or so we've ridden him this summer over 4 days. Used Gloves work fine for that, and I do the hoof trimming, anyway. So there's no waiting for a farrier, or paying one.
I'll say this: they don't make great "replacements" for lost shoes. They'll work for that, but you'll wonder how people use them, and you'll have to stop now and then to put them back on after they pop off. They're much better as a primary form of hoof protection. Like that, with a hoof/boot combo that fits, they are really great protection.
And yes, really, don't worry about removing them daily. Open the gaiter, check for rubs, and put the gaiter back on.
My thought is I could ride for 2 or 3 days, take them off and reuse them the next time I come up. During the hunting season I am usually there for about 10 days and I could just leave them on during that time frame.
Here's the issue ... fit can be tough. They used to have "Fit Kits" ... worth the money if they still do that. Sure, you can buy them at the local feed store, where there'll be a limited choice in sizes, but I'd deal directly with EasyCare.
Most of the time, for light riding, you could possibly get away with just boots on the front, depending on how rocky things are up there for you.
Don't forget the athletic tape idea ... really helps, IMO. And check out their blog. Lots of good ideas.